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Book
17 p. : digital, PDF file.
Despite decades of research on the reactivity and stable isotope properties of Fe oxides, the ability to describe the redox behavior of Fe oxides in the environment is still quite limited. This is due, in large part, to the analytical and spatial complexities associated with studying microscopic processes at the Fe oxide-water interface. This project had the long-term vision of filling this gap by developing a detailed understanding of the relationship between interfacial ET processes, surface structure and charge, and mineral semiconducting properties. We focused on the Fe(III)-oxides and oxyhydroxides because of their geochemical preponderance, versatility in synthesis of compositionally, structurally, and morphologically tailored phases, and because they are amenable to a wide range of surface and bulk properties characterization. In particular, reductive transformation of phases such as hematite (α-Fe<sub>2</sub>O<sub>3</sub>) and goethite (α-FeOOH) in aqueous solution can serve as excellent model systems for studies of electron conduction processes, as well as provide valuable insights into effect of nanoscale conductive materials on contaminant fate at DOE sites. More specifically, the goal of the Iowa component of this project was to use stable Fe isotope measurements to simultaneously measure isotope specific oxidation states and concentrations of Fe at the hematite-water and goethite-water interface. This work builds on our previous work where we used an innovative combination of <sup>57</sup>Fe Mössbauer spectroscopy and high precision isotope ratio measurements (MC-ICP-MS) to probe the dynamics of the reaction of aqueous Fe(II) with goethite. Mössbauer spectroscopy detects <sup>57</sup>Fe only among all other Fe isotopes and we have capitalized on this to spectroscopically demonstrate Fe(II)-Fe(III) electron transfer between sorbed Fe(II) and Fe(III) oxides (Handler, et al., 2009; Gorski, et al. 2010; Rosso et al., 2010). By combining the Mössbauer spectroscopy and stable isotopes measurements, we have been able to simultaneously track the oxidation state and isotope concentration of the bulk Fe oxide and aqueous Fe. One of our most compelling findings is that despite the apparent stability of the Fe(II)-goethite system, there is actually a tremendous amount of Fe atom cycling occurring between the aqueous phase and the bulk goethite as indicated by the isotopic composition of both phases approaching the mass balance average (Handler et al., 2009). How such extensive re-crystallization and Fe atom exchange can occur with no significant morphological change is a fascinating question. Based on previous work from PI Rosso’s group showing that a potential gradient across hematite crystal faces leads to conduction through hematite and growth and dissolution at separate crystal faces we proposed that a redox-driven recrystallization could be occurring that would explain the extensive mixing observed with the isotope data. From our previous studies utilizing Mössbauer spectroscopy, we know that sorption of Fe(II) onto goethite results in electron transfer between the sorbed Fe(II) and the structural Fe(III) in goethite. Oxidation of the sorbed Fe(II) produces growth of goethite on goethite (i.e., homoepitaxy), as well as injection of an electron into goethite. It is possible that electron transfer from sorbed Fe(II) occurs across a potential gradient, and that Fe(II) atoms are dissolved at a different location on the goethite surface. These newly-reduced Fe(II) atoms could then dissolve into the aqueous phase, exposing fresh Fe(III) goethite to the aqueous phase. Through a repeated series of these five steps of sorption–electron transfer–crystal growth–conduction– dissolution, a redox-driven conveyor belt, could be established that would allow all of the goethite to be eventually exposed to the aqueous phase and exchanged. This surface-mediated recrystallization process would result in similar Fe isotope distributions i...
Book
1 online resource (p. 2825–2831 ) : digital, PDF file.
<sup>13</sup>C-Metabolic Flux Analysis (<sup>13</sup>C-MFA) is rapidly being recognized as the authoritative method for determining fluxes through metabolic networks. Site-specific <sup>13</sup>C enrichment information obtained using NMR spectroscopy is a valuable input for <sup>13</sup>C-MFA experiments. Chemical shift overlaps in the 1D or 2D NMR experiments typically used for <sup>13</sup>C-MFA frequently hinder assignment and quantitation of site-specific <sup>13</sup>C enrichment. Here we propose the use of a 3D TOCSY-HSQC experiment for <sup>13</sup>C-MFA. We employ Non-Uniform Sampling (NUS) to reduce the acquisition time of the experiment to a few hours, making it practical for use in <sup>13</sup>C-MFA experiments. Our data show that the NUS experiment is linear and quantitative. Identification of metabolites in complex mixtures, such as a biomass hydrolysate, is simplified by virtue of the <sup>13</sup>C chemical shift obtained in the experiment. In addition, the experiment reports <sup>13</sup>C-labeling information that reveals the position specific labeling of subsets of isotopomers. As a result, the information provided by this technique will enable more accurate estimation of metabolic fluxes in larger metabolic networks.
Book
9 p. : digital, PDF file.
<p>We report here the synthesis of a neutral viologen derivative, C<sub>24</sub>H<sub>16</sub>N<sub>2</sub>O<sub>4</sub>·2H<sub>2 </sub>O. The non-solvent portion of the structure (<italic>Z</italic>-Lig) is a zwitterion, consisting of two positively charged pyridinium cations and two negatively charged carboxylate anions. The carboxylate group is almost coplanar [dihedral angle = 2.04 (11)°] with the benzene ring, whereas the dihedral angle between pyridine and benzene rings is 46.28 (5)°. The<italic>Z</italic>-Lig molecule is positioned on a center of inversion (Fig. 1). The presence of the twofold axis perpendicular to the<italic>c</italic>-glide plane in space group<italic>C</italic>2/c generates a screw-axis parallel to the<italic>b</italic>axis that is shifted from the origin by 1/4 in the<bold>a</bold>and<bold>c</bold>directions. This screw-axis replicates the molecule (and solvent water molecules) through space. The<italic>Z</italic>-Lig molecule links to adjacent molecules<italic>via</italic>O—H...O hydrogen bonds involving solvent water molecules as well as intermolecular C—H...O interactions. There are also π–π interactions between benzene rings on adjacent molecules.</p>
Book
1 online resource (11 p. ) : digital, PDF file.
This is a Laboratory Analytical Procedure (LAP) for bio-oil analysis.
Book
1 online resource.
An acid-functionalized polyolefin material that can be used as an acid catalyst in a wide range of acid-promoted chemical reactions, wherein the acid-functionalized polyolefin material includes a polyolefin backbone on which acid groups are appended. Also described is a method for the preparation of the acid catalyst in which a precursor polyolefin is subjected to ionizing radiation (e.g., electron beam irradiation) of sufficient power and the irradiated precursor polyolefin reacted with at least one vinyl monomer having an acid group thereon. Further described is a method for conducting an acid-promoted chemical reaction, wherein an acid-reactive organic precursor is contacted in liquid form with a solid heterogeneous acid catalyst comprising a polyolefin backbone of at least 1 micron in one dimension and having carboxylic acid groups and either sulfonic acid or phosphoric acid groups appended thereto.
Book
1 online resource (12 p. ) : digital, PDF file.
In this study, the Fischer-Tropsch synthesis (FTS) reaction is one of the most promising processes to convert alternative energy sources, such as natural gas, coal or biomass, into liquid fuels and other high-value products. Despite its commercial implementation, we still lack fundamental insights into the various deactivation processes taking place during FTS. In this work, a combination of three methods for studying single catalyst particles at different length scales has been developed and applied to study the deactivation of Co/TiO<sub>2</sub> Fischer-Tropsch synthesis (FTS) catalysts. By combining transmission X-ray microscopy (TXM), scanning transmission X-ray microscopy (STXM) and scanning transmission electron microscopy-electron energy loss spectroscopy (STEM-EELS) we visualized changes in the structure, aggregate size and distribution of supported Co nanoparticles that occur during FTS. At the microscale, Co nanoparticle aggregates are transported over several μm leading to a more homogeneous Co distribution, while at the nanoscale Co forms a thin layer of ~1-2 nm around the TiO<sub>2</sub> support. The formation of the Co layer is the opposite case to the “classical” strong metal-support interaction (SMSI) in which TiO<sub>2</sub> surrounds the Co, and is possibly related to the surface oxidation of Co metal nanoparticles in combination with coke formation. In other words, the observed migration and formation of a thin CoO<sub>x</sub> layer are similar to a previously discussed reaction-induced spreading of metal oxides across a TiO<sub>2</sub> surface.
Book
1 online resource.
  • Employing 'second generation' matrices.- (MA)LDI MS mass spectrometry imaging at high specificity and sensitivity.- Techniques for fingermark analysis using MALDI MS - a practical overview.- Whole/Intact Cell MALDI MS Biotyping in Mammalian Cell Analyis.- MALDI biotyping for microorganism identification in clinical microbiology.- Future applications of MALDI-TOF MS in microbiology.- MALDESI: Fundamentals, direct analysis, and MS imaging.- Microprobe MS Imaging of Live Tissues, Cells, and Bacterial Colonies using LAESI.- Efficient production of multiply charged MALDI ions.- Food Authentication by MALDI MS - MALDI-TOF MS Analysis of Fish Species.- Quantitative MALDI MS using Ionic Liquid Matrices.- Disease profiling by MALDI MS analysis of biofluids.- Ionic Liquids and other liquid matrices for sensitive MALDI MS analysis.- Coupling liquid MALDI MS to liquid chromatography.
  • (source: Nielsen Book Data)9783319048185 20160619
This book covers the state-of-the-art of modern MALDI (matrix-assisted laser desorption/ionization) and its applications. New applications and improvements in the MALDI field such as biotyping, clinical diagnosis, forensic imaging, and ESI-like ion production are covered in detail. Additional topics include MS imaging, biotyping/speciation and large-scale, high-speed MS sample profiling, new methods based on MALDI or MALDI-like sample preparations, and the advantages of ESI to MALDI MS analysis. This is an ideal book for graduate students and researchers in the field of bioanalytical sciences. This book also: * Showcases new techniques and applications in MALDI MS * Demonstrates how MALDI is preferable to ESI (electrospray ionization) * Illustrates the pros and cons associated with biomarker discovery studies in clinical proteomics and the various application areas, such as cancer proteomics.
(source: Nielsen Book Data)9783319048185 20160619
The current invention describes methods and compositions of various sorbents based on aerogels of various silanes and their use as sorbent for carbon dioxide. Methods further provide for optimizing the compositions to increase the stability of the sorbents for prolonged use as carbon dioxide capture matrices.
Book
1 online resource.
Systems for converting aldose sugars to ketose sugars and separating and/or concentrating these sugars using differences in the sugars' abilities to bind to specific affinity ligands are described.
Book
1 online resource (3 p. ) : digital, PDF file.
This report documents a Pu isotopic analysis.
Book
1 online resource.
Provided in one embodiment is an electrochemical cell, comprising: (i) a plurality of electrodes, comprising a fuel electrode that comprises aluminum and an air electrode that absorbs gaseous oxygen, the electrodes being operable in a discharge mode wherein the aluminum is oxidized at the fuel electrode and oxygen is reduced at the air electrode, and (ii) an ionically conductive medium, comprising an organic solvent; wherein during non-use of the cell, the organic solvent promotes formation of a protective interface between the aluminum of the fuel electrode and the ionically conductive medium, and wherein at an onset of the discharge mode, at least some of the protective interface is removed from the aluminum to thereafter permit oxidation of the aluminum during the discharge mode.
Book
1 online resource (15 p. ) : digital, PDF file.
The degradation of Antifoam 747 to form flammable decomposition products has resulted in declaration of a Potential Inadequacy in the Safety Analysis (PISA) for the Defense Waste Processing Facility (DWPF). Savannah River National Laboratory (SRNL) testing with simulants showed that hexamethyldisiloxane (HMDSO), trimethylsilanol (TMS), and 1-propanal are formed in the offgas from the decomposition of the antifoam. A total of ten DWPF condensate samples from Batch 735 and 736 were analyzed by SRNL for three degradation products and additional analytes. All of the samples were analyzed to determine the concentrations of HMDSO, TMS, and propanal. The results of the organic analysis found concentrations for propanal and HMDSO near or below the detection limits for the analysis. The TMS concentrations ranged from below detection to 11 mg/L. The samples from Batch 736 were also analyzed for formate and oxalate anions, total organic carbon, and aluminum, iron, manganese, and silicon. Most of the samples contained low levels of formate and therefore low levels of organic carbon. These two values for each sample show reasonable agreement in most cases. Low levels of all the metals (Al, Fe, Mn, and Si) were present in most of the samples.
Book
1 online resource (26 p. ) : digital, PDF file.
The Bioenergy Program at Pacific Northwest National Laboratory (PNNL) is evaluating the feasibility of converting wastewater sludge materials to fuels. Wastewater sludge from various municipalities will be used in the evaluation process and as with any municipal waste, there is the potential for residual contaminates to remain in the sludge following wastewater treatment. Many surveys and studies have confirmed the presence of pharmaceuticals in municipal wastewater and effluents (World Health Organization, 2011). Determination of the presence and concentrations of the contaminants is required to define the proper handling of this sludge. A list of targeted compounds was acquired from the literature and an analytical method was developed for the pharmaceutical and personal care compounds. The presence of organics complicated the analytical techniques and, in some cases, the precision of the results. However, residual concentrations of a range of compounds were detected in the wastewater sludge and the presence and concentrations of these compounds will be considered in identifying the appropriate handling of this material in conduct of research.
Book
1 online resource (9 p. ) : digital, PDF file.
LANL has been contacted to provide possible assistance in safe disposition of a number of <sup>241</sup>Am-bearing materials associated with local industrial operations. Among the materials are ion exchange resins which have been in contact with <sup>241</sup>Am and nitric acid, and which might have potential for exothermic reaction. The purpose of this paper is to analyze and define the resin forms and quantities to the extent possible from available data to allow better bounding of the potential reactivity hazard of the resin materials. An additional purpose is to recommend handling procedures to minimize the probability of an uncontrolled exothermic reaction.
Book
16 p. : digital, PDF file.
Savannah River National Laboratory analyzed samples from Tank 38H and Tank 43H to support Enrichment Control Program and Corrosion Control Program. The total uranium in the Tank 38H samples ranged from 20.5 to 34.0 mg/L while the Tank 43H samples ranged from 47.6 to 50.6 mg/L. The U-235 percentage ranged from 0.62% to 0.64% over the four samples. The total uranium and percent U-235 results appear consistent with previous Tank 38H and Tank 43H uranium measurements. The Tank 38H plutonium results show a large difference between the surface and sub-surface sample concentrations and a somewhat higher concentration than previous sub-surface samples. The two Tank 43H samples show similar plutonium concentrations and are within the range of values measured on previous samples. The plutonium results may be biased high due to the presence of plutonium contamination in the blank samples from the cell sample preparations. The four samples analyzed show silicon concentrations ranging from 47.9 to 105 mg/L.
Book
1 online resource.
Book
115 pages : illustrations ; 23 cm
A volume in the Emerging Issues in Analytical Chemistry series, published in partnership with RTI International and edited by Brian F. Thomas, The Analytical Chemistry of Cannabis: Quality Assessment, Assurance, and Regulation of Medicinal Marijuana and Cannabinoid Preparations provides analytical chemistry methods that address the latest issues surrounding cannabis-based products. The plethora of marketed strains of cannabis and cannabinoid-containing products, combined with the lack of industry standards and labelling requirements, adds to the general perception of poor quality control and limited product oversight. The methods described in this leading-edge volume help to support the manufacturing, labelling, and distribution of safe and consistent products with known chemical content and demonstrated performance characteristics. It treats analytical chemistry within the context of the diverse issues surrounding medicinal and recreational cannabis in a manner designed to foster understanding and rational perspective in non-scientist stakeholders as well as scientists who are concerned with bringing a necessary degree of order to a field now characterized by confusion and contradiction. * Addresses current and emerging analytical chemistry methods-an approach that is unique among the literature on this topic* Presents information from a broad perspective of the issues in a single compact volume* Employs language comprehensible to non-technical stakeholders as well as to specialists in analytical chemistry.
(source: Nielsen Book Data)9780128046463 20160619
Biology Library (Falconer)
Book
1 online resource (5 volumes) : illustrations (some color)
  • Volume 1. Liquid chromatography
  • volume 2. Special liquid chromatography modes and capillary electromigration techniques
  • volume 3. Gas, supercritical and chiral chromatography
  • volume 4. Chromatographic and related techniques
  • volume 5. Sample treatment, method validation, and applications.
Book
Article No. 21660 : digital, PDF file.
Within the BaFe<sub>2</sub>As<sub>2</sub> crystal lattice, we partially substitute thallium for barium and report the effects of interlayer coupling in Ba<sub>1-x</sub>Tl<sub>x</sub>Fe<sub>2</sub>As<sub>2</sub> crystals. We demonstrate the unusual effects of magneto-elastic coupling and charge doping in this iron-arsenide material, whereby Néel temperature rises with small x, and then falls with additional x. Specifically, we find that Néel and structural transitions in BaFe<sub>2</sub>As<sub>2</sub> (TN = T<sub>s</sub> = 133 K) increase for x = 0.05 (T<sub>N</sub> = 138 K, T<sub>s</sub> = 140 K) from magnetization, heat capacity, resistivity, and neutron diffraction measurements. Evidence from single crystal X-ray diffraction and first principles calculations attributes the stronger magnetism in x = 0.05 to magneto-elastic coupling related to the shorter intraplanar Fe-Fe bond distance. With further thallium substitution, the transition temperatures decrease for x = 0.09 (T<sub>N </sub>= T<sub>s</sub> = 131 K), and this is due to charge doping. Finally, we illustrate that small changes related to 3d transition-metal state can have profound effects on magnetism.
Book
1 online resource.
The disclosure discloses abrasion resistant, persistently hydrophobic and oleophobic, anti-reflective and anti-soiling coatings for glass. The coatings described herein have wide application, including for example the front cover glass of solar modules. Methods of applying the coatings using various apparatus are disclosed. Methods for using the coatings in solar energy generation plants to achieve greater energy yield and reduced operations costs are disclosed. Coating materials are formed by combinations of hydrolyzed silane-base precursors through sol-gel processes. Several methods of synthesis and formulation of coating materials are disclosed.

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